What does fault code ECM-P003973 mean?

Diagnostic fault code details for ECM-P003973 (Volvo S60 (2011–), Volvo S60 (2011–), Volvo S80 (2007–)). Repair service at OBD Tuning.

VOLVO

ECM-P003973 - Turbocharger/Supercharger Bypass Valve "A" Control Circuit Range/Performance. Mechanical Failures. Actuator stuck closed

System

Engine Control Module (ECM)

Volvo models this fault code applies to

Applies to the following models:

6 models

S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V70 (2008–)

Show models by year and engine (11)

What does this fault code mean?

The actuator for turbo bypass valve A has stuck in the closed position. The fault is mechanical and shows when the engine control module expects the valve to open but it does not.

Possible causes

Mechanical fault where the actuator for bypass valve A is stuck in the closed position
The valve is binding in its position and cannot move to open

What you can do

1Check that the fuses for the turbo control are intact. Their locations are given in the instruction manual
2With a diagnostic tool, activate bypass valve A and listen for the actuator to move. No movement suggests it is stuck
3Inspect the linkage to the valve for damage, wear and dirt
4Have a workshop with diagnostic equipment check the actuator and the control signals to the valve
5Repair what is found, clear the code and road test the car to see whether it returns

Symptoms you may notice2

Noise while driving, especially just after the accelerator pedal is released
The noise may be heard at some times or all the time, which cannot be predicted

General guidance for car owners. Diagnosis on the car can point to a different cause.